Yamaha F225A Service Manual page 220

LOWR
NOTE:
• Select the shim thickness (T'4) by using the
specified measurement(s) and the calcula-
tion formula.
• Measure the taper roller bearing at three
points to find the height average.
Shimming plate 2: 90890-06701
Digital caliper 3: 90890-06704
2. Install the thrust bearing 4 to the propel-
ler shaft 5, and then measure the pro-
peller shaft flange and thrust bearing
thickness (M7) as shown.
3. Calculate the propeller shaft shim thick-
ness (T4) as shown in the examples
below.
6-59
Lower unit
S69J6626
NOTE:
"A" and "B" are the deviation of the propeller
shaft housing dimension from standard. The
"A" mark a and "B" mark b are stamped on
the propeller shaft housing in 0.01 mm units.
If the "A" mark or "B" mark is unreadable,
assume that "A" and "B" are zero and check
the free play when the unit is assembled.
Calculation formula 1:
Propeller shaft shim thickness (T4) =
29.00 + A/100 – B/100 – M6 – M7
Example:
If "M6" is 15.73 mm and "M7" is 12.50 mm
and "A" is (+6) and "B" is (–5), then
T4 = 29.00 + (+6)/100 – (–5)/100 – 15.73 – 12.50 mm
= 29.00 + 0.06 + 0.05 – 15.73 – 12.50 mm
= 0.88 mm
4. Round the numerals for the propeller
shaft shim(s) (T4) as follows.
Calculated numeral
at 1/100 place
1, 2
3, 4, 5
6, 7, 8
9, 10
Example:
If "T4" is 0.88 mm, then the propeller shaft
shim is 0.85 mm.
If "T4" is 0.90 mm, then the propeller shaft
shim is 0.88 mm.
5. Calculate and select the propeller shaft
shim thickness (T'4) as shown in the
examples below.
Calculation formula 2:
Propeller shaft shim thickness (T'4) =
T4 – 0.30
Example:
If "T4" is 0.85 mm, then
T'4 = 0.85 – 0.30 mm
= 0.55 mm
Rounded numeral
0
2
5
8
69J3D11